The University of Maryland Electron Ring: A Platform For Study of Galactic Dynamics on a Laboratory Scale

The University of Maryland electron ring (UMER) is a novel experimental storage ring designed to investigate the dynamics of large systems of collisionless particles that nevertheless interact via collective mechanisms. Heavily diagnosed and designed to circulate a 100 mA electron beam at 10 keV for several turns, UMER allows us to follow the evolution of the beam over a large number of dynamical periods. Given the similarity of dynamics between the Coulomb forces and gravitational forces, it is possible to design beam experiments that will simulate such astrophysical events as galactic merger, for instance. The cross-comparison of beam experiments with accelerator simulation codes provides invaluable benchmarks of transient processes akin to, for example, violent relaxation in stellar systems that are otherwise impossible to obtain.

Prognosis of unprotected left main coronary artery stenting and the factors affecting the outcomes in Chinese

BACKGROUND

The long term prognosis of unprotected left main coronary artery (LMCA) stenting is controversial. This study was conducted to evaluate the immediate and long term outcomes of LMCA stenting in Chinese patients and to determine which factors affect the outcomes.

METHODS

From May 1997 to March 2003, 224 patients in 23 hospitals underwent elective unprotected LMCA stenting with bare metal stents. Their clinical records were analysed to ascertain immediate and long term outcomes of LMCA stenting as well as factors influencing the prognosis.

RESULTS

Stents were implanted into LMCA successfully in 223 cases (99.6 %). One death (0.5%) and one case of non-Q wave nonfatal myocardial infarction (MI) occurred in hospital. The mean follow-up time was (15.6 +/- 12.3) months. Cardiac death developed in 10 cases (4.5%), noncardiac death in 2 cases (0.9%), nonfatal MI in 4 cases (1.8%), target lesion revascularization (TLR) of LMCA in 26 cases (11.7%) and TLR of nonLMCA in 37 cases (16.5%). Univariate analysis showed that cardiac death correlated with left ventricular ejection fraction (LVEF < 40%), female gender and LMCA combined with multivessel disease; that major adverse cardiac events (MACE) correlated with LVEF < 40%, bifurcation lesion and incomplete revascularization. Logistic regression analysis revealed that LVEF < 40% and female gender were independent predictors of cardiac death and MACE. Follow-up angiography was performed in 102 cases (45.7%). The restenosis rate was 31.4%.

CONCLUSIONS

Long-term outcomes of stenting for selected patients with unprotected LMCA stenosis is acceptable. It should be performed in inoperable or low risk patients with LVEF > or = 40% and isolated LMCA disease or LMCA combined with multivessel diseases in whom complete revascularization can be obtained.

[The effect of early invasive strategy on early and late outcomes in high-risk non-ST-segment elevation acute coronary syndromes]

OBJECTIVE

To investigate the effect of early invasive strategy on early and late outcomes in high-risk patients with non-ST-segment elevation acute coronary syndromes (ACS).

METHODS

Five hundred and forty-five patients of ACS without ST-segment elevation were randomly assigned to an early conservative strategy (284 cases) or early invasive strategy group (261 cases), who were enrolled consecutively from Oct., 2001 to Oct., 2003. The combined cardiovascular events (a combination of cardiac death, nonfatal myocardial infarction, nonfatal heart failure and hospital readmission due to recurrent ischemic angina) within 30 days and 6 months were analyzed and the effects of early invasive strategy on early and late outcomes in high-risk patients with increased TnI or hs-CRP levels were evaluated.

RESULTS

As compared with early conservative strategy, early invasive strategy lowered the rate of hospital readmission due to recurrent ischemic angina of 30 d and the combined cardiovascular events of 30 d and 6 months (all P < 0.05). Subgroup analysis indicated early invasive strategy could significantly decrease the incidences of the combined cardiovascular events of 30 d and 6 months and the hard end point events of 6 months in patients with increased TnI or hs-CRP levels (all P < 0.01), but no such changes could be seen in patients with normal TnI or hs-CRP levels, as compared with early conservative strategy.

CONCLUSIONS

Early invasive strategy decreases significantly cardiovascular events and improves the early and late outcomes in high-risk patients with increased TnI or hs-CRP levels.

PON1 polymorphism, diabetes mellitus, obesity, and risk of myocardial infarction: Modifying effect of diabetes mellitus and obesity on the association between PON1 polymorphism and myocardial infarction

PURPOSE

Previous studies on PON1 gene polymorphism and the risk of coronary atherosclerotic diseases have been inconsistent. This may be in part due to population difference in prevalence of high oxidative stress and its modifying effect on the association. Diabetes and obesity are two major risk factors of myocardial infarction (MI) and associated with high oxidative stress. We investigated the association between PON1 Q192R polymorphism and the risk of myocardial infarction (MI) and in particular, whether the association can be modified by diabetes mellitus (DM) and obesity.

METHODS

We conducted a case-control study, including 154 MI cases and 154 controls enrolled in Beijing, China. Epidemiological and clinical data and PON1 Q192R genotype were obtained from each subject.

RESULTS

Without considering the modifying effect of DM and obesity, PON1 Q192R polymorphism was not associated with MI. When simultaneously examining the joint association of this polymorphism, DM, and obesity with MI, as compared to subjects with QQ genotypes and without DM and obesity, subjects with QR/RR genotypes and with either DM or obesity had significantly higher risk of MI (OR = 3.6, 95% CI: 1.5-8.7).

CONCLUSION

Our data suggest that PON1 Q192R polymorphism was not independently associated with MI but further increased the risk of MI among the subjects with DM, obesity, or both, the conditions associated with high oxidative stress.

Beta2 adrenergic receptor gene Arg16Gly polymorphism is associated with therapeutic efficacy of benazepril on essential hypertension in Chinese

BACKGROUND

There is considerable variability in individual response to antihypertensive agents. The reason for this is not known, but may be related to individual genetic variability. This study examined whether the therapeutic efficacy of benazepril on essential hypertension is modified by beta2 adrenergic receptor gene (ADRB2) Arg16Gly (R16G) polymorphism.

METHODS AND RESULTS

We conducted a family-based study of 321 and 610 hypertensive subjects from Yuexi and Huoqiu Counties of Anhui, China, respectively. Both systolic and diastolic blood pressures (SBP and DBP) before and after a 15-day benazepril treatment were measured. ADRB2 R16G genotypes were determined for all subjects. ADRB2 G16 allele frequency was found to be 41.0% and. 47.4% in Huoqiu and Yuexi, respectively. In Yuexi family-based association test (FBAT) revealed that the G16 allele was associated with a greater DBP decrease in response to a 15-day benazepril treatment (Z = 2.12, P = 0.03), and the data were consistent with a dominant inheritance model. A similar trend was observed in Huoqiu Chinese, but the magnitudes of effects were smaller and did not reach statistical significance. The FBAT results were further confirmed by using a generalized estimating equation model.

CONCLUSION

Our family-based study provided the first evidence that ADRB2 R16G polymorphism may play an important role in DBP response to benazepril treatment, although the magnitude of the effect appears to be modified by other risk factors such as plasma lipid and glucose profiles.

Modeling of Noninvasive Microwave Characterization of Breast Tumors

This paper describes an approach for the noninvasive microwave characterization of tumors in breast tissue. Tumors are modeled as lossy dielectric targets. Their complex natural resonances (CNR) can be extracted from the time-domain response and correlated with diagnostically useful properties. Finite-difference time-domain simulation is used to obtain the time-domain response from a tumor with a short electromagnetic pulse as an input. The normal breast tissue and tumor are modeled as dispersive media using the Debye model and CNRs are extracted using Prony's method. It is shown that the locations of the dominant CNRs are separated in the complex frequency plane as functions of the tumor dielectric properties. The technique has potential as a diagnostic tool to characterize breast lesions in conjunction with other imaging modalities such as ultrasound for detection.

Hypertensive patients from two rural Chinese counties respond differently to benazepril: the Anhui Hypertension Health Care Study

PURPOSE

Essential hypertension, as a complex disorder with unknown etiology cause, is a major public health problem worldwide. Patients need constant drug therapy to maintain their blood pressure in a normal range. However, the current facts suggest that the treatment is not optimized in a large number of patients, and as a result they are at risk for compliance resulting in uncontrolled blood pressure. Genetic and environmental factors associated with individual variation in response to anti-hypertensive drug remain largely unknown.

METHODS

In order to illustrate the existence and to attempt to identify the factors modifying drug effect, we conducted a large-scale follow-up study in two Chinese rural counties differing in both genetic background and residential environment. Hypertensive patients were treated with benazepril, a commonly used angiotensin converting enzyme inhibitor, for 15 days, and the end-point effect was evaluated.

RESULTS

We found that there were large and significant differences in drug response between subjects from two counties, even after adjustment for known factors. The responses to benazepril, measured in diastolic blood pressure drop, in male patients from Yuexi was twice as effective as their counterparts from Huoqiu.

CONCLUSIONS

These results suggest that adjustment of treatment regimen is necessary to improve efficacy, and it could be done at the population level to make it more feasible and affordable.

D919G polymorphism of methionine synthase gene is associated with blood pressure response to benazepril in Chinese hypertensive patients

Individual variation in drug response is considered to have multiple origins arising from interactions among susceptible genes and environmental factors. A total of 726 hypertensive patients who took benazepril 10 mg once a day for 15 days and their families from Huoqiu county of Anhui Province, China, were used to study the association between D919G polymorphism of methionine synthase (MTR) gene and the antihypertensive effect of this angiotensin-converting enzyme inhibitor. Compared to the 919D allele, both population-based ( P=0.010) and family-based association tests (additive model P=0.018, dominant model P=0.025) demonstrated that the 919G allele was associated with a significantly less diastolic blood pressure reduction. No significant association was found between the extent of systolic blood pressure reduction and benazepril therapy. Our finding suggests that the D919G polymorphism of the MTR gene may be a useful genetic marker to predict the antihypertensive effect of short-term benazepril therapy in hypertensive patients of Anhui Province, China.

Five haplotypes account for fifty-five percent of ATM mutations in Brazilian patients with ataxia telangiectasia: seven new mutations

We have studied the molecular genetics of 27 Brazilian families with ataxia telangiectasia (AT). Five founder effect haplotypes accounted for 55.5% of the families. AT is an autosomal recessive disorder of childhood onset characterized by progressive cerebellar ataxia, ocular apraxia, telangiectasia, immunodeficiency, radiation sensitivity, chromosomal instability, and predisposition to cancer. The ATM gene spans more than 150 kb on chromosome region 11q23.1 and encodes a product of 3056 amino acids. The ATM protein is a member of the phosphatidylinositol 3-kinase (PI-3K) family of proteins and is involved in cell cycle control and DNA repair pathways. DNA was isolated from lymphoblastoid cell lines and haplotyped using four STR markers (D11S1818, NS22, D11S2179, D11S1819) within and flanking the ATM gene; all allele sizes were standardized in advance. In addition to the STR haplotypes, SNP haplotypes were determined using 10 critical polymorphisms. The entire gene was screened sequentially by protein truncation testing (PTT), single strand conformation polymorphism (SSCP), and then denaturing high performance liquid chromatography (dHPLC) to identify the disease-causing mutations. Of the expected 54 mutations, 50 were identified. All mutations but one, led to a truncated or null form of the ATM protein (nonsense, splice site, or frameshift). Five families (18.5%) carried a deletion of 3450nt (from IVS28 to Ex31), making this one of the two most common Brazilian mutations. Mutations were located throughout the entire gene, with no clustering or hotspots. Standardized STR haplotype analysis greatly enhanced the efficiency of mutation screening.

[The protective effect of interleukin-1 receptor antagonist on postischemic reperfused myocardium and its possible mechanism]

OBJECTIVE

To observe the dynamic changes of plasma inflammatory cytokine interleukin-1 beta (IL-1 beta) in patients with acute myocardiac infarction (AMI) before and after recanalization of the infarct related artery (IRA) and to observe the effect of recombinant human IL-1 receptor antagonist (rhIL-1ra) on the postischemic reperfused myocardium in experimental rabbits.

METHODS

(1) ELISA was used to measure the plasma IL-1 beta of 22 AMI patients, 20 males and 2 females, aged 64 +/- 12, before emergency percutaneous coronary intervention (PCI), and 12 hours and 24 hours after-intervention, and measure the plasma IL-1 beta of 8 healthy controls, 6 males and 2 females, aged 56 +/- 9. (2) Forty rabbits underwent ligation of the left circumflex branch of coronary artery (LCX) for 50 minutes and reperfusion for 4 hours after the ligatures were untied. The rabbits were randomly divided into 4 groups of 10 rabbits to be injected into the left ventricle immediately before the reperfusion with rhIL-1ra 10 mg/kg (group A), 20 mg/kg (group B), or 40 mg/kg (group C), and normal saline (control group) respectively. After reperfusion of 4 hours, the LCX was re-ligated. Evans blue was injected into the left ventricle. 15% KCl was injected intravenously to kill the rabbits. Their hearts were taken out to weigh the non-ischemic, ischemic, and necrotic cardiac muscles so as to calculate the infarct size. The myoperoxidase (MPO) activity was measured by colorimetry. Sections of myocardium were made. The number of apoptotic cardiomyocytes was evaluated by TUNEL method. The apoptotic rate of cardiomyocyte was measured by annexin V method. The DNA expression of myocardium was detected by DNA laddering method. The expressions of Bcl-2 and Bax apoptosis genes were assessed.

RESULTS

(1) The average plasma IL-1 beta level of the 22 AMI patients before emergency PCI was significantly higher than that of the controls (28 pg/ml +/- 9 pg/ml vs. 20 pg/ml +/- 11 pg/ml, P < 0.05), and became the highest 12 hours after the intervention (86 pg/ml +/- 14 pg/ml), and the high level lasted to 24 hours after emergency PCI. (2) In the ischemia-reperfusion rabbit model, the infarct size was 47% +/- 7% in the group A, 34% +/- 8% in the group B, 31% +/- 6% in the group C, and 61% +/- 11% in the control group (P < 0.05, 0.01, and 0.01 respectively). The activity of myocardial MPO was 16.6 +/- 3.6 min(-1).g.w.w(-1) in the group A, 10.9 min(-1).g.w.w(-1) +/- 1.9 min(-1).g.w.w(-1) in the group B, 7.8 min(-1).g.w.w(-1) +/- 2.2 min(-1).g.w.w(-1) in the group C, and 20.5 min(-1).g.w.w(-1) +/- 4.5 min(-1).g.w.w(-1) in the control group (P < 0.05, 0.01, and 0.01 respectively). The cardiomyocyte apoptosis evaluated by TUNEL was 38.3 n/HP +/- 7.4 n/HP in the group A, 25.6 n/HP +/- 6.8 n/HP in the group B, 12.2 n/HP +/- 3.3 n/HP in the group C, and 44.4 n/HP +/- 9.5 n/HP in the control group (P < 0.05, and P < 0.01 respectively in comparison between the group B and the control group and between the group C and the control group). The apoptotic rate by annexin V method was 11.6% +/- 2.7% in the group A; 7.7% +/- 2.4% in the group B, 4.7% +/- 1.4% in the group C, and 15.6% +/- 3.5% in the control group (P < 0.05, 0.01, and 0.01 respectively). DNA electrophoresis showed scaling ladder pattern only in the control group. The fluorescent density of the apoptosis gene Bax in myocardium was 24.9 +/- 8.2 in the group A; 15.5 +/- 3.4 in the group B, 10.6 +/- 2.5 in the group C, and 33.3 +/- 9.4 in the control group (P = 0.0298, 0091, and 0052 respectively) and no significant difference in the expression of Bcl-2 was shown among the 4 groups. Myocardial MPO was correlated with cardiomyocyte apoptosis (r = 0.86 by TUNEL, P < 0.01; r = 0.75 by Annexin V method, P < 0.05).

CONCLUSION

Inflammatory cytokine IL-1 beta is involved in myocardial ischemia-reperfusion injury. With potential therapeutic value in prevention and treatment of ischemia-reperfusion injury to myocardium, rhIL-1ra may reduce myocardial ischemia-reperfusion injury by suppression of cardiomyocytes apoptosis mediated by IL-als; 0.86 by TUNEL, P < 0.01; r = 0.75 by Annexin V method, P < 0.05).

CONCLUSION

Inflammatory cytokine IL-1 beta is involved in myocardial ischemia-reperfusion injury. With potential therapeutic value in prevention and treatment of ischemia-reperfusion injury to myocardium, rhIL-1ra may reduce myocardial ischemia-reperfusion injury by suppression of cardiomyocytes apoptosis mediated by IL-1.

The association between paired basic amino acid cleaving enzyme 4 gene haplotype and diastolic blood pressure

BACKGROUND

In a previously identified locus linked to hypertension on chromosome 15q, we identified three blood pressure candidate genes: insulin-like growth factor 1 receptor gene (IGF1R), myocyte specific enhancer factor 2A gene (MEF2A), and paired basic amino acid cleaving enzyme 4 gene (PACE4). In this study, we tested their associations with hypertension using haplotype analysis.

METHODS

A total of 288 unrelated individuals, including 163 high diastolic blood pressure (DBP) subjects and 125 normal DBP subjects were enrolled in this case-control study. Twenty single nucleotide polymorphisms (SNPs) in the three genes were genotyped using polymerase chain reaction followed by restriction enzyme digestion. Haplotype analysis was accomplished in the following stages: (1) pair-wise linkage disequilibrium test among SNPs on the same gene was performed to explore blocks in which recombination is very unlikely to happen; (2) Estimation-Maximization algorithm was applied to estimate haplotype frequencies in each block; (3) the chi-square test was used to examine the specific haplotype difference, and a permutation test was used to examine the overall haplotype profile difference between cases and controls in each block.

RESULTS

An estimated haplotype "CCCCG" frequency in the haplotype block on the PACE4 gene was significantly higher in high DBP cases than in controls (P < 0.01). The overall estimated haplotype profile in this block was also significantly different between the cases and the controls (P < 0.001). This association indicates.

CONCLUSIONS

This study for the first time demonstrated that PACE4 gene may play an important role in the regulation of DBP. This association indicates that variations influencing DBP resides in or near this genomic region.

Polymorphism K469E of intercellular adhesion molecule-1 gene and restenosis after coronary stenting in Chinese patients

BACKGROUND

Inflammation is a major cause of restenosis after coronary stenting. Intercellular adhesion molecule-1 (ICAM-1) is an important adhesion molecule that plays a key role in the tight adhesion between leukocytes and vascular endothelium. The object of this study was to investigate the association between the K469E polymorphism of the ICAM-1 gene and restenosis after coronary stenting in North Chinese population.

METHODS

The ICAM-1 K469E polymorphism was genotyped using polymerase chain reaction-restriction fragment length polymorphism method in 124 patients who had undergone coronary stenting and coronary angiography at least 3 months earlier. Information on clinical risk factors and procedure-related data were also collected.

RESULTS

Of 124 enrolled patients in total, there were 72 cases of in-stent restenosis. The restenosis rate in this population was 58.1%. The frequencies of the three possible genotypes of the ICAM-1 K469E polymorphism were: KK genotype 50.8%, EE genotype 41.9%, and EK genotype 41.9%. Among restenosis patients, the frequency of the KK genotype was 58.3% and the frequency of E allele carriers was 41.7%. Among non-restenosis patients, the frequency of the KK genotype was 40.4%, and the frequency of E allele carriers was 59.6%. The distribution of these two genotype groups between restenosis and non-restenosis patients was significantly different (P = 0.049). Using multivariate logistic regression, the difference between the two groups was more apparent. The odds ratio of KK homozygotes vs E allele carriers was 2.6, with 95% confidence interval 1.2 - 5.8 (P = 0.018). After grading of risk factors, we found that the KK genotype was a stronger predictor of in-stent restenosis in obesity or hyperlipemia patients, with an odds ratio of 9.3 and 3.7, respectively (P < 0.05).

CONCLUSION

In our study population, KK homozygotes of the ICAM-1 codon 469 mutation had a higher risk of restenosis after coronary stenting, especially in the case of obese or hyperlipemia patients.

Linkage of bipolar affective disorder on chromosome 8q24: follow-up and parametric analysis

Our group first reported a linkage finding for bipolar (BP) disorder on chromosome 8q24 in a study of 50 multiplex pedigrees, with an HLOD score reaching 2.39. Recently, Cichon et al reported an LOD score of 3.62 in the same region using two-point parametric analysis. Subsequently, we published the results of a genome scan for linkage to BP disorder using a sample extended to 65 pedigrees in which chromosome 8q24 provided the best finding, an NPL score of 3.13, approaching the accepted score for suggestive linkage. We have now fine mapped this region of chromosome 8 in our 65 pedigrees by the addition of 19 microsatellite markers reaching a marker density of 0.8 cM and an information content of 0.84. After the addition of the new data, the original NPL score slightly increased to 3.25. Two-point parametric analysis using the model employed by Cichon et al obtained an LOD score of 3.32 for marker D8S256 at theta=0.14 exceeding the proposed threshold for genomewide significance. After adjusting the parameters in accordance with the 'common disease-common variant' hypothesis, multipoint parametric analysis resulted in an HLOD of 2.49 (alpha=0.78) between D8S529 and D8S256, and defined a 1-LOD interval corresponding to a 2.3 Mb region. No allelic association with the disease was observed for our set of microsatellite markers. Biologically, plausible candidate genes in this region include thyroglobulin, KCNQ3 coding for a voltage-gated potassium channel and the gene for brain adenyl-cyclase (ADCY8).

[Relation between inflammation related cytokines and myocardial microcirculatory reperfusion state]

OBJECTIVE

To observe the dynamic fluctuation of inflammatory cytokines (IL-1beta, TNFalpha) and anti-inflammatory cytokine (IL-10) in acute myocardial infarct (AMI) patients before and after recanalization of infarct related artery (IRA) and analyze the relationship between fluctuation of cytokines and reperfusion state of myocardial tissue.

METHODS

(1) In 22 AMI patients and 8 healthy subjects, plasma IL-1beta, TNFalpha and IL-10 were measured with ELISA before emergency percutaneous coronary interposition (PCI), 12 h and 24 h post-intervention. (2) The 22 AMI patients were further divided into 2 groups according to ST-segment change in ECG at 2h after reperfusion: group A, good reperfusion of myocardium, ST decrease >or= 70% (n = 12) and group B, poor reperfusion of myocardium, ST decrease < 70% (n = 10). The change of plasma levels of IL-1beta, TNFalpha and IL-10 of the two groups was compared.

RESULTS

(1) Plasma TNFalpha and IL-10 in group A and B were not significantly higher those that the healthy controls (P > 0.05) before emergency PCI, but IL-1beta was significantly higher (P < 0.05). Plasma IL-1beta and TNFalpha in group A and B and IL-10 in group B at 12 h and 24 h post-intervention were significantly higher than those before PCI (P < 0.01, P < 0.05, P < 0.05), while IL-10 in group A was not (P > 0.05). (2) Plasma IL-1beta, TNFalpha and IL-10 in group B were not higher than those in group A before PCI, but they were significantly higher at 12 h post-PCI (P < 0.01, P < 0.05, P < 0.05) and IL-1beta and IL-10 were still higher at 24 h post-PCI (P < 0.05). The increment of IL-10 was significantly less than that of IL-1beta and TNFalpha in group A and B (P < 0.01, P < 0.05).

CONCLUSIONS

Cytokines may be involved in myocardial ischemia-reperfusion injury and increase of inflammatory cytokines may be a marker of poor myocardial microcirculatory reperfusion.

Investigation of opportunistic pathogens in municipal drinking water under different supply and treatment regimes

Changing regulations to lower disinfectant byproducts in drinking water is forcing utilities to switch disinfection from chlorine to monochloramine. It is generally unknown whether this will impact positively or negatively on the microbiological quality of drinking water. A utility in Florida, using water with relatively high organic carbon levels from deep wells in several wellfields, made the decision to change its disinfection regime from chlorine to chloramine in order to meet the new regulations. To assess the impacts of such a change on the microbiology of its water supplies, it undertook a number of studies before and after the change. In particular, the presence of the opportunistic pathogens Legionella and Mycobacterium, and also the composition of drinking-water biofilms, were examined. A preliminary synthesis and summary of these results are presented here. Legionella species were widely distributed in source waters and in the distribution system when chlorine was the disinfectant. In some samples they seemed to be among the dominant biofilm bacteria. Following the change to monochloramine, legionellae were not detected in the distribution system during several months of survey; however, they remained detectable at point of use, although with less species diversity. A variety of mycobacteria (21 types) were widely distributed in the distribution system when chlorine was the disinfectant, but these seemed to increase in dominance after chloramination was instituted. At point of use, only four species of mycobacteria were detected. Other changes occurring with chloramination included (a) an altered biofilm composition, (b) increased numbers of total coliforms and heterotrophs and (c) nitrification of water storage tanks. The results suggested that consideration should be given to the microbiological effects of changing disinfection regimes in drinking-water and distribution system biofilms.

Integrated modeling of microwave food processing and comparison with experimental measurements

This paper presents an integrated electromagnetic and thermal model for the microwave processing offood packages. The model is developed by combining the edge finite element formulation of the 3-D vector electromagnetic field in the frequency domain and the node finite element solution of the thermal conduction equation. Both mutual and one-way coupling solution algorithms are discussed. Mutual coupling entails the iterative solution of the electromagnetic field and the thermal field, because the physical properties are temperature-dependent. The one-way coupling is applicable when the properties are temperature independent or this dependence is weak. Mesh sensitivity and shape regularity for the edge element based formulation for computational electromagnetics are discussed in light of available analytical solutions for a simple wave guide. The integrated model has been used to study the electromagnetic and thermal phenomena in a pilot scale microwave applicator with and without the food package immersed in water. The calculated results are compared with the experimentally measured data for the thermal fields generated by the microwave heating occurring in a whey protein gel package, and reasonably good agreement between the two is obtained.

[Cardiac presentations in patients with SARS]

OBJECTIVE

To investigate the impact of SARS on heart initially.

METHODS

The clinical and laboratory data of 86 patients with SARS were collected and analyzed statistically.

RESULTS

In recovery phase, the rest heart rates in 64% of patients with SARS exceeded 90 bpm, and the heart rates after mild exercises in 72.1% of patients with SARS exceeded 100 bpm.

CONCLUSION

SARS, which mainly resulted in pulmonary damage, may involve heart.

[Expression of chemokine-like factor 2 (CKLF2) mRNA in the rat myocardium after myocardial infarction]

OBJECTIVE

To investigate the expression of chemokine-like factor 2 (CKLF2) mRNA in the rat myocardium after myocardial infarction (MI).

METHODS

In a rat model of MI, the myocardium surrounding the infarcted area was used for RNA preparation at different time points. After RT, competitive polymerase chain reaction amplification was performed to assess the expression of rCKLF2 mRNA. SAS Kruskal-Wallis test was used for statistical comparisons.

RESULTS

The gene expression of rCKLF2 at mRNA level was significantly increased in the myocardium surrounding the infarcted area 3 days, 1 week, 2 weeks after infarction.

CONCLUSION

It is possible that CKLF2 contributes to the pathophysiological process and needs to be further investigated.

Trapping and sequence analysis of 1138 putative exons from human chromosome 18

In a search for novel genes on chromosome 18 (HC18), on which several regions have been linked to bipolar disorder, we applied exon trapping to HC18-specific cosmids. Among the 1138 exons trapped, 1052 of them have been mapped to HC18, and the remaining 86 have not been localized. No exons were localized to genomic regions other than HC18. BLAST database search revealed that 190 exons were identical to 98 Unigenes on HC18; 98 identical to additional 82 clusters of ESTs not present in the HC18 Unigene set; 39 homologous to genes from human and other species (e<10(-3)); and the remaining 811 exons had no significant homology to transcripts in public databases. The mapped exons were compared to the 867 annotated genes on HC18 in the Celera databases; 216 exons were identical to 104 Celera 'genes' and the remaining 836 exons were not found in the Celera databases. On average, there were two exons for a matched transcript (known genes and ESTs). Therefore, the 850 novel exons may represent hundreds of novel genes on chromosome 18.

Genome-wide scan of bipolar disorder in 65 pedigrees: supportive evidence for linkage at 8q24, 18q22, 4q32, 2p12, and 13q12

The purpose of this study was to assess 65 pedigrees ascertained through a Bipolar I (BPI) proband for evidence of linkage, using nonparametric methods in a genome-wide scan and for possible parent of origin effect using several analytical methods. We identified 15 loci with nominally significant evidence for increased allele sharing among affected relative pairs. Eight of these regions, at 8q24, 18q22, 4q32, 13q12, 4q35, 10q26, 2p12, and 12q24, directly overlap with previously reported evidence of linkage to bipolar disorder. Five regions at 20p13, 2p22, 14q23, 9p13, and 1q41 are within several Mb of previously reported regions. We report our findings in rank order and the top five markers had an NPL>2.5. The peak finding in these regions were D8S256 at 8q24, NPL 3.13; D18S878 at 18q22, NPL 2.90; D4S1629 at 4q32, NPL 2.80; D2S99 at 2p12, NPL 2.54; and D13S1493 at 13q12, NPL 2.53. No locus produced statistically significant evidence for linkage at the genome-wide level. The parent of origin effect was studied and consistent with our previous findings, evidence for a locus on 18q22 was predominantly from families wherein the father or paternal lineage was affected. There was evidence consistent with paternal imprinting at the loci on 13q12 and 1q41.

Insulin sensitivity and the diffuseness of coronary artery disease in humans

OBJECTIVE

To study the relationship between insulin sensitivity and diffuse coronary artery disease.

METHODS

Ninety-two consecutive patients underwent coronary angiography were enrolled in the study. Relationships between the results of angiograms and both glucose tolerance and blood lipids were analyzed.

RESULTS

The mean age of the 92 patients (70 males, 22 females) was 65.4 +/- 6.3 y. In the 78 patients diagnosed by angiography as coronary artery disease, diffuse lesion was more common in diabetic patients than in those without a diabetes history (12/13 vs 24/65, P = 0.00026). Fasting glucose [(6.06 +/- 2.43) x 10(-3) mol/L vs (4.80 +/- 1.47) x 10(-3) mol/L, P = 0.009], glucose levels at one hour [(12.37 +/- 4.38) x 10(-3) mol/L vs (9.10 +/- 3.97) x 10(-3) mol/L, P = 0.001], two hours [(11.12 +/- 5.64) x 10(-3) mol/L vs (7.49 +/- 4.29) x 10(-3) mol/L, P = 0.003] and three hours [(8.11 +/- 5.51) x 10(-3) mol/L vs (5.56 +/- 3.46) x 10(-3) mol/L, P = 0.020] after food were higher in patients with diffuse coronary disease than in those with non-diffuse coronary disease. Differences in the insulin sensitivity index (ISI) between the two groups was statistically significant (-4.36 +/- 0.52 vs -3.89 +/- 0.69, P = 0.003). The incidence of multiple-vessel disease in diabetic patients was higher than that in non-diabetic patients (12/13 vs 33/65, P = 0.00565). Glucose levels at two hours [(10.22 +/- 5.57) x 10(-3) mol/L vs (7.67 +/- 4.43) x 10(-3) mol/L, P = 0.034] and three hours [(7.90 +/- 5.47) x 10(-3) mol/L vs (5.22 +/- 2.79) x 10(-3) mol/L, P = 0.007] after food were higher in patients with multiple-vessel disease than in those with single-vessel disease. Impaired insulin sensitivity without a history of diabetes mellitus was commonly seen in patients with coronary artery disease.

CONCLUSIONS

The diffuseness of coronary artery disease is associated with insulin sensitivity and blood glucose levels. Insulin resistance is a common phenomenon in non-diabetic patients.

Four novel mutations associated with autosomal recessive inclusion body myopathy (MIM: 600737)

Recently, mutations in the gene encoding for the bi-functional enzyme UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE/MNK), symbol GNE or GLCNE (MIM: 603824) [EC 5.1.3.14], were associated with IBM2 (MIM: 600737). IBM2 is a recessively inherited vacuolar myopathy with a prevalence rate of 1-2/1000 amongst people of Iranian-Jewish descent. Seven missense mutations were previously described by Eisenberg et al. All families tested from Iranian and Middle Eastern Jewish ancestry have the same homozygous mutation (bp2186t>c). Here we review the mutations in GNE associated with IBM2, and we describe additional four mutations found in individuals suffering from clinically similar disorder who are not of Iranian or Jewish descent. These findings further confirm that homozygous or compound heterozygous mutations of GNE/MNK gene associated with IBM2 are not confined to any single specific region of the enzyme outside its negative feedback regulatory domain located at codons 249-275.

Early diagnosis of ataxia-telangiectasia using radiosensitivity testing

OBJECTIVES

To utilize radiosensitivity testing to improve early diagnosis of patients with ataxia-telangiectasia (A-T).

STUDY DESIGN

We established normal ranges for the colony survival assay (CSA) by testing cells from 104 patients with typical A-T, 29 phenotypic normal patients, and 19 A-T heterozygotes. We also analyzed 61 samples from patients suspected of having A-T and 25 patients with related disorders to compare the CSA with other criteria in the diagnosis of A-T.

RESULTS

When cells were irradiated with 1.0 Gy, the mean survival fraction (microSF +/- 1 SD) for patients with A-T was 13.1% +/- 7.2% compared with 50.1% +/- 13.5% for healthy control patients. These data served to define a diagnostic range for the CSA (ie, <21%), a normal range (>36%), and a nondiagnostic intermediate range of 21% to 36%. The mutations of patients with A-T with intermediate radiosensitivity tended to cluster around the functional domains of the ATM gene.

CONCLUSIONS

The CSA is a useful adjunctive test for confirming an early clinical diagnosis of A-T. However, CSA is also abnormal in other chromosomal instability and immunodeficiency disorders.

[Focal adhesion kinase and mitogen activated protein kinase are involved in vascular smooth muscle cells migration and proliferation stimulated by fibronectin]

OBJECTIVE

To study the roles of focal adhesion kinase (FAK) and mitogen activated protein kinase (p42/44MAPK) in the process of migration and proliferation of vascular smooth muscle cells (VSMC) stimulated by fibronectin (FN).

METHODS

VSMCs were taken from the tunica media of SD rats and cultured. Migration and proliferation of cultured VSMCs were stimulated by different concentrations of FN; FAK, p42/44MAPK and their phosphorylation were detected by immunoprecipitation and Western blot. FAK antisense oligodeoxynucleotide (ODN) was transfected into VSMCs by cationic lipid to investigate its modulatory effects on tyrosine phosphorylation. VSMC migration and proliferation were also measured by modified Boyden Chamber and (3)H-thymidine respectively.

RESULTS

FAK and p42/44MAPK were expressed when VSMC adhesion and migration were successfully simulated by FN (5, 10, 20, 40, and 60 microg/ml), high contents of FAK and p42/44MAPK phosphorylation were detected in groups with 20 microgram/ml FN or more. FAK antisense ODN was transfected efficiently by cationic lipid. Phosphorylation of FAK and p42/44MAPK was inhibited significantly after FAK antisense ODN transfection. Cell migration stimulated by FN of the concentrations of 10, 20, 40, and 60 microg/ml was reduced by 23.26%, 21.63%, 19.31% and 17.88% respectively (P < 0.05). VSMC proliferation in 5 approximately 60 microgram/ml FN groups was reduced by 27.67% approximately 46.67% (P < 0.05).

CONCLUSION

FAK and p42/44MAPK play an important role in VSMC migration and proliferation stimulated by extracellular matrix. The process can be inhibited by FAK antisense ODN effectively.

[FAK antisense oligodeoxynucleotides inhibit vascular smooth muscle cell migration and adhesion mediated by FAK-ERK1/2 signaling pathway]

AIM

To study the effects of FAK-ERK1/2 signaling pathway and FAK antisense oligodeoxynucleotides (ODNs) on vascular smooth muscle cell (SMC) migration and adhesion stimulated by fibronectin (FN).

METHODS

Migration and adhesion of cultured SMCs were stimulated by different concentrations of FN, FAK, ERK1/2. And their phosphorylation were detected by immunoprecipitation and Western blot. FAK antisense ODNs were transfected into SMCs by cationic lipid to investigate its modulatory effects on tyrosine phosphorylation, SMCs migration and adhesion were also measured by modifing Boyden Chamber and morphological enumeration, respectively.

RESULTS

FAK were expressed when SMCs adhesion and migration were successfully simulated by FN (5, 10, 20, 40, 60 micrograms.mL-1), high contents of FAK and ERK1/2 phosphorylation were detected by 20 micrograms.mL-1 FN or more. FAK antisense ODNs were transfected efficiently by cationic lipid. FAK and ERK1/2 phosphorylation were inhibited magnificently after FAK antisense ODNs transfection. Cell migration stimulated by FN 10, 20, 40 and 60 micrograms.mL-1 were reduced by 23.26%, 21.63%, 19.31% and 17.88% respectively (P < 0.05). SMCs adhesive spreading in 5-60 micrograms.mL-1 FN groups were reduced by 17.89%-27.67% (P < 0.05).

CONCLUSION

FAK-ERK1/2 mediated signal transduction play important roles in SMCs migration and adhesion stimulated by extracellular matrix. The process can be inhibited by FAK antisense ODNs effectively.

Activated focal adhesion kinase involved in adhesion and migration of vascular smooth muscle cells stimulated by fibronectin

OBJECTIVE

To study the effects of focal adhesion kinase (FAK) phosphorylation on smooth muscle cells (SMCs) adhesion and migration stimulated by fibronectin.

METHODS

Adhesion and migration of cultured SMCs were stimulated by different concentrations of fibronectin (FN), FAK and its phosphorylation were detected by immunoprecipitation and Western blot. FAK antisense oligodeoxynucleotides (ODNs) were transfected into SMCs by cationic lipid to investigate its modulatory effects on tyrosine phosphorylation. SMCs adhesion and migration were also measured by morphological enumeration and modified Boyden Chambers, respectively.

RESULTS

FAK were expressed when SMCs adhesion and migration were successfully simulated by different concentrations of FN. FAK phosphorylation were detected only at 20 microg/ml FN or more. FAK antisense ODNs were transfected efficiently by cationic lipid and FAK phosphorylation was inhibited substantially. The SMCs migration rate in the 5 - 60 microg/ml FN groups was reduced by 17.89% - 27.67%. Cell migration stimulated by FN at 10, 20, 40 and 60 microg/ml were reduced by 23.26%, 21.63%, 19.31% and 17.88%, respectively (P < 0.05).

CONCLUSIONS

FAK phosphorylation and FAK-mediated signal transduction play important roles in SMCs adhesion and migration stimulated by ECM. The process can be inhibited effectively by FAK antisense ODNs.

Use of cutting balloons in coronary interventions

OBJECTIVE

To study the efficacy and safety of cutting balloons in coronary interventions.

METHODS

Twenty-two patients with 23 narrowed coronary arteries and 25 lesions enrolled the study, 17 of whom had 18 diseased coronary arteries and 18 lesions were in-stent restenosis. The average time from previous stenting was 7.60 +/- 3.53 months. The lesions were dilated with cutting balloons.

RESULTS

All of the lesions were dilated successfully by 5.16 +/- 2.30 inflations of a cutting balloon. The mean total duration of balloon inflation was 233.96 +/- 94.83 seconds at pressures up to 9.40 +/- 1.96 bars. The severity of vascular stenosis was lessened substantially (89.64 +/- 8.65% vs 17.60 +/- 17.15%, P = 0.000) without severe complications. Three restenotic lesions were further dilated with conventional balloons, another one was stented again because of a dissection distal to the previous stent. Three primary lesions were stented for dissection or residual stenosis. Angina pectoris reoccurred in two patients in a mean follow-up period of 7.42 +/- 6.87 (range 0.5-20) months.

CONCLUSION

Cutting balloon dilation is an effective and safe choice in interventions for coronary disease especially for in-stent restenosis.

NEDD4L on human chromosome 18q21 has multiple forms of transcripts and is a homologue of the mouse Nedd4-2 gene

The validation of full-length cDNA represents a crucial step in gene identification and subsequent functional analysis. In searching for candidate genes for bipolar disorder on chromosome 18q21, a novel gene homologous to NEDD4 (Neural precursor cells expressed developmentally down-regulated) was identified using exon trapping and cDNA cloning. This novel gene is termed NEDD4L (Human Gene Nomenclature Committee symbol). Typical NEDD4 orthologues that contain a C2 (Ca(2+)/lipid-binding) and a HECT (Homologous to the E6-AP Carboxyl Terminus) ubiquitin-protein ligase domain, and multiple WW domains have been shown to regulate the epithelial sodium channel (ENaC). In mice, Nedd4 has two distinct isoforms termed Nedd4-1 that belongs to the typical NEDD4 class, and Nedd4-2 that is homologous to Nedd4-1 but lacks the C2 domain. NEDD4L contains the WW and HECT domains seen in the NEDD4 gene family, but lacks the C2 domain in the N-terminus. BLAST database search showed that the deduced polypeptide of NEDD4L has 97 and 62% sequence identity to mouse Nedd4-2 and human NEDD4, respectively. Multiple forms of transcripts of NEDD4L have been isolated, which differ in transcription start and termination sites together with the presence or absence of an alternative spliced exon. Northern blot analysis showed a 3.4 kb mRNA species was specifically expressed in heart and skeletal muscle, while a 3.2 kb band and/or an additional 3.6 kb band is seen in other tissues tested. Striking homology of NEDD4L to mouse Nedd4-2 suggests it is the human homologue of mouse Nedd4-2. Its position in a region of linkage for autosomal dominant orthostatic hypotensive disorder and its potential role in regulating ENaC make NEDD4L a candidate gene for this disorder.

[Influence of interleukin-10 on nitric oxide /nitric oxide synthase system of the aorta]

To study the influence of the inflammatory factor---interleukin-10 on nitric oxide (NO) and nitric oxide synthase system of rat aorta, Griess assay, production of (3)H-citrulline and Western blot were used to determine the release of NO, and the activity and expression of nitric oxide synthase, respectively. The results showed that lipopolysaccharide (LPS) stimulated the activity of inducible nitric oxide synthase (iNOS) and the release of NO. 10(-10) 10(-8) g/ml of IL-10 induced the activity and expression of endothelial nitric oxide synthase (eNOS), but not of iNOS. 10(-9) 10(-8) g/ml of IL-10 also downloaded the release of NO, and the activity and expression of iNOS induced by LPS, while 10(-7) g/ml of IL-10 significantly stimulated the activity and expression of iNOS but not eNOS. In summary, IL-10 presents a duple role in NO/NOS system. On the one hand, IL-10 inhibits the activity and expression of iNOS induced by inflammatory factor; on the other hand, IL-10 stimulates the release of endothelial NO.

The chemokine KC, but not monocyte chemoattractant protein-1, triggers monocyte arrest on early atherosclerotic endothelium

In a reconstituted flow chamber system, preincubation with chemokines can trigger the arrest of rolling monocytes, suggesting that this interaction could help recruit these cells to early atherosclerotic lesions. To date, however, the contribution of endothelium-derived chemokines found in these lesion to monocyte arrests has not been investigated. The endothelium of lesion-prone carotid arteries from apolipoprotein E-deficient (ApoE(-/-)) mice, but not control mice, presents the chemokines KC (mouse GRO-alpha) and JE (mouse monocyte chemoattractant protein-1 [MCP-1]). Arrest of a monocytic cell line or mouse blood monocytes perfused through carotid arteries of ApoE(-/-) mice was reduced by treating with either pertussis toxin, an antagonist of CXCR2, or an antibody to KC, but this process was insensitive to agents that blocked CCR-2 or JE. Conversely, monocyte accumulation more than doubled upon pre-perfusion of the carotid artery with KC but not with mouse MCP-1. Blockade of alpha(4)beta(1) integrin (VLA-4) or vascular cell adhesion molecule-1, but not CD18 or intercellular adhesion molecule-1, almost completely inhibited the arrest of monocytes. We conclude that when presented by early atherosclerotic lesions, KC but not murine MCP-1 triggers VLA-4-dependent monocyte recruitment.

Interleukin 10 inhibits the rat VSMC proliferation and collagen secretion stimulated by angiotensin II

OBJECTIVE

To study the effect of interleukin 10 (IL-10) on the angiotensin II (AngII) stimulated rat VSMC proliferation and collagen secretion, and furthermore, explore its mechanism.

METHODS

On cultured VSMC of rat, 3H-thymine (3H-TdR) and 3H-proline incorporations were used to evaluate the DNA and collagen synthesis, respectively. Western blot and immunoprecipitation were applied to assay the expression and activity of focal adhesion kinase (FAK), respectively.

RESULTS

IL-10 (10(-8) approximately 10(-10) g/ml) inhibited the increase of 3H-TdR and 3H-proline incorporation as well as FAK activity, which was induced by 10(-7) mol/L AngII (P < 0.05 or P < 0.01). IL-10 also obviously downregulated the synthesis and secretion of collagen by AngII stimulated VSMC. But there was no difference in the protein expression of FAK among all the groups (P > 0.05).

CONCLUSION

IL-10 antagonizes the VSMC proliferation and collagen synthesis by regulating FAK activity stimulated by AngII.

Adhesion molecules and atherogenesis

Atherosclerosis is an inflammatory disease of the vessel wall characterized by monocyte infiltration in response to pro-atherogenic factors such as oxidized lipids. Recently, the role of specific adhesion molecules in this process has been explored. The endothelium overlying atherosclerotic lesions expresses P-selectin and the shoulder regions express vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), which is also expressed on endothelium in regions not prone to plaque development. Serum levels of soluble P-selectin, ICAM-1 and VCAM-1 are elevated in patients with angina pectoris or peripheral atherosclerotic disease. Reconstituted in vitro systems using monocytes on cytokine-activated endothelial cells under shear flow suggested the involvement of P-selectin, L-selectin, VCAM-1, its ligand, VLA-4 integrin and CD18 integrins. Studies of monocyte adhesion in isolated perfused carotid arteries harvested from atherosclerotic (apoE-/-) mice show a predominant involvement of P-selectin and its ligand P-selectin glycoprotein-1 (PSGL-1) in rolling and of VLA-4 and VCAM-1 in firm adhesion. Consistent with these findings, apoE-/- mice that are also deficient for P-selectin show significantly reduced atherosclerotic lesion sizes and are almost completely protected from neointimal growth after vascular injury. Milder effects are also seen in the low-density lipoprotein (LDL) receptor deficient (LDLR-/-) mouse. In a high cholesterol/cholate model, a role of ICAM-1 and CD18 integrins was also shown, but this awaits confirmation in more physiologic models. Transient blockade of the VLA-4/VCAM-1 adhesion pathway by antibodies or peptides in apoE-/- or LDLR-/- mice reduced monocyte and lipid accumulation in lesions. These data suggest that P-selectin, PSGL-1, VLA-4 and VCAM-1 are the most important adhesion molecules involved in monocyte recruitment to atherosclerotic lesions.

[Influence of myocardial ischemia/reperfusion in vitro on nuclear envelope NTPase activity and mRNA export in the cardiomyocyte of rabbits]

AIM

To study the alteration of nuclear envelope associated NTPase activity and mRNA nucleocytoplasmic transport in rabbit cardiomyocyte following in vitro ischemia and reperfusion.

METHODS

The model of myocardial perfusion in rabbit was used to produce myocardial I/R injury and cardiomyocyte nuclear envelope vesicles were prepared by density gradient centrifugation for the assay of mRNA transport rate and NTPase activity.

RESULTS

NTPase activity was reduced and mRNA transport rate was significantly decreased in I/R (P < 0.01) but not in ischemia group( P > 0.05).

CONCLUSION

The nuclear envelope vesicles had been injured following ischemia and reperfusion and resulted in NTPase activity reduced and egress of mRNA interrupted, and therefore may lead to decreasing of protein synthesis.

RANTES deposition by platelets triggers monocyte arrest on inflamed and atherosclerotic endothelium

BACKGROUND

Circulating platelets and chemoattractant proteins, such as the CC chemokine RANTES, contribute to the activation and interaction of monocytes and endothelium and may thereby play a pivotal role in the pathogenesis of inflammatory and atherosclerotic disease.

METHODS AND RESULTS

The binding of RANTES to human endothelial cells was detected by ELISA or immunofluorescence after perfusion with platelets or exposure to their supernatants. Monocyte arrest on endothelial monolayers or surface-adherent platelets was studied with a parallel-wall flow chamber and video microscopy. We show that RANTES secreted by thrombin-stimulated platelets is immobilized on the surface of inflamed microvascular or aortic endothelium and triggers shear-resistant monocyte arrest under flow conditions, as shown by inhibition with the RANTES receptor antagonist Met-RANTES or a blocking RANTES antibody. Deposition of RANTES and its effects requires endothelial activation, eg, by interleukin-1beta, and is not supported by venous endothelium or adherent platelets. Immunohistochemistry revealed that RANTES is present on the luminal surface of carotid arteries of apolipoprotein E-deficient mice with early atherosclerotic lesions after wire-induced injury or cytokine exposure. In a mechanistic model of atherogenesis, monocyte adherence on endothelium covering such lesions was studied in murine carotid arteries perfused ex vivo, showing that the accumulation of monocytic cells in these carotid arteries involved RANTES receptors.

CONCLUSIONS

The deposition of RANTES by platelets triggers shear-resistant monocyte arrest on inflamed or atherosclerotic endothelium. Delivery of RANTES by platelets may epitomize a novel principle relevant to inflammatory or atherogenic monocyte recruitment from the circulation.

L-selectin shedding regulates leukocyte recruitment

The physiologic role of L-selectin shedding is unknown. Here, we investigate the effect of L-selectin shedding on firm adhesion and transmigration. In a tumor necrosis factor alpha-induced model of inflammation, inhibition of L-selectin shedding significantly increased firm adhesion and transmigration by a lymphocyte function-associated antigen (LFA)-1 and intercellular adhesion molecule (ICAM)-1-dependent mechanism. We examined the quality of leukocyte rolling and L-selectin-mediated signaling. Blockade of L-selectin shedding significantly reduced the "jerkiness" of leukocyte rolling, defined as the variability of velocity over time. A low level of jerkiness was also observed in the rolling of microbeads conjugated with L-selectin, a model system lacking the mechanism for L-selectin shedding. Inhibition of L-selectin shedding potentiated activation of LFA-1 and Mac-1 induced by L-selectin cross-linking as shown by activation epitope expression and binding of ICAM-1-conjugated beads. We conclude that inhibition of L-selectin shedding increases leukocyte adhesion and transmigration by (a) increasing leukocyte exposure to the inflamed endothelium by decreasing jerkiness and (b) promoting leukocyte activation by outside-in signaling. These observations help to resolve the apparent discrepancy between the minor contribution of L-selectin to rolling and the significant leukocyte recruitment defect in L-selectin knockout mice.

Simulation of field characteristics of the focused axisymmetrically curved surface transducers

The acoustical fields produced by a variety of focused axisymmetrically curved surface transducers with large aperture have been investigated on the basis of Fresnel-Kirchhoff diffraction theory. The interrelation of ultrasound characteristics with some structural aspects of the transducers has been calculated and compared. The forms of resulting intensity maxima and their resulting suitability for surgical lesion of tissues are compared through parameters such as "lesioning capability" and "focussing efficiency." Although only modest changes in intensity distribution are possible, some may have applications in making lesions for control of focal cancer and other pathologies.

192Ir endovascular irradiation prevents restenosis after balloon angioplasty in rabbit

OBJECTIVE

To examine the effect of endovascular irradiation on restenosis after balloon angioplasty in rabbit.

METHODS

After the establishment of rabbit iliac atherosclerosis model, balloon angioplasty was performed at the lesion segment of the iliac artery. Rabbits were randomly divided into three groups: control group, 10 Gy irradiated group and 18 Gy irradiated group. Endovascular irradiation was performed for irradiated groups at the dilated sites by introducing the 192Ir radioactive guidewire through a catheter. After four weeks, the animals were killed and the target segments were cut down. Histopathologic and morphometric analyses were carried out.

RESULTS

The mean final lumen area in the 18 Gy group was larger than that in the control or 10 Gy group (P < 0.05). The intimal area in the 18 Gy group was smaller (P < 0.05).

CONCLUSIONS

192Ir endovascular irradiation may prevent restenosis after balloon angioplasty. The effect is related to the delivered dose. The mechanism is involved in inhibition of neointimal proliferation.

Gene identification using exon amplification on human chromosome 18q21: implications for bipolar disorder

We previously reported linkage between bipolar disorder and a region on human chromosome (HC) 18q21. To identify genes in this region, exon trapping was performed on cosmids isolated from an HC18-specific cosmid library (LL18NC02) using 47 sequence tagged site (STS) markers from 18q21 as hybridization probes. A total of 285 unique sequences (exons) were obtained from 850 sequenced clones. Homology searching of the databases using NCBI's BLAST algorithms revealed that 31 exons have identity to known genes and/or ESTs, seven are identical to regions of finished genomic sequences in the 18q21 region, 20 have significant similarity (>30% sequence identity) to genes from human and/or other species, 19 were repetitive sequences, and 208 sequences (72%) are novel. Seventy per cent of the trapped sequences were predicted to be derived from genes using library screening and RT-PCR analyses. This represents an initial stage in characterizing genes in a susceptibility region for further study in bipolar disorder or other diseases that map to this region.

Role of vascular cell adhesion molecule-1 and fibronectin connecting segment-1 in monocyte rolling and adhesion on early atherosclerotic lesions

Atherosclerotic lesion development seems to be inflammatory in nature and involves the recruitment of monocytes to the vessel wall. In this study, we investigated the role of vascular cell adhesion molecule-1 (VCAM-1) and fibronectin (FN) connecting segment-1 containing the amino acid sequence ILDV as functional ligands for alpha(4)beta(1) integrin (VLA-4) in monocyte rolling and adherence to early atherosclerotic lesions. Carotid arteries of apolipoprotein E-deficient mice were isolated and perfused with monocytes or U937 cells. Cell adhesion was reduced 95+/-4% by monoclonal antibodies HP1/2 and HP2/1, which block VLA-4 binding to both VCAM-1 and FN connecting segment-1. mAb HP1/3 preferentially blocked interaction of VLA-4 with FN but not VCAM-1 and decreased adhesion by 30+/-8%. In contrast, blocking VCAM-1 by perfusing the isolated carotid artery with mAb MK-2.7 reduced adhesion by 75+/-12%. Mononuclear cell adhesion to the early atherosclerotic endothelium was inhibited by 68+/-10% in the presence of EILDVPST but not in the presence of control peptide EIDVLPST. When VLA-4 or VCAM-1 was blocked, more mononuclear cells rolled on early lesions at significantly higher (approximately doubled) rolling velocities. These data demonstrate that (1) blockade of VCAM-1 can abrogate the majority (75+/-12%) of VLA-4-dependent monocyte adhesion on early atherosclerotic endothelia and (2) ILDV peptide interferes with VLA-4 binding to both VCAM-1 and FN and may be useful in limiting monocyte adhesion to atherosclerotic lesions.

An experimental study of endovascular brachytherapy using liquid 32P filled balloon catheter

OBJECTIVE

To observe the effect of endovascular brachytherapy on the prevention of restenosis after interveneional therapy and to investigate its possible mechanisms.

METHODS

In the balloon-injuried rabbit model, pathological sections of iliac arteries were observed and the changes of vascular histomorphology were estimated by computer analysis of photomicrograms. Using immunohistochemical techniques, proliferating cell nuclear antigen (PCNA) was quantified to assess the proliferation of vascular smooth muscle cells.

RESULTS

After rabbit iliac arteries were injured by balloon overstretch angioplasty, neointima were shown to be less proliferative in the irradiated group than in the control group, from PCNA scores. The formation of neointima was suppressed with the external elastic laminar area increasing and without the luminal area decreasing in the irradiation group.

CONCLUSION

Endovascular brachytherapy using a liquid 32P filled balloon catheter system could prevent restenosis possibly by inhibiting the formation of neointima and improving positive vascular remodeling.

Seroprevalence against Norwalk-like human caliciviruses in beijing, China

Serum specimens from 1,109 individuals at different ages in Beijing, China, were collected between April 1996 and March 1997 and tested for IgG antibodies against human caliciviruses using enzyme immune assays (EIAs). Baculovirus-expressed recombinant Norwalk virus (rNV) and Mexican virus (rMxV) capsid proteins were used as antigens. The seroprevalence was 89% for rNV and 91% for rMxV. Similar seroprevalence between the two antigens was observed in individual age groups and both genders. Infants had a high seroprevalence (99% for NV and 94% for MxV) at birth. The lowest seroprevalence (41% for rNV and 36% for rMxV) was at 7-11 months of age. A sharp increase in seroprevalence occurred in early childhood, with 65% and 70% at one, 85% and 90% at three, and 100% and 98% at 8-9 years of age for rNV and rMxV, respectively. Forty-three individuals had antibody against rNV but not rMxV and 63 individuals had antibody against rMxV but not rNV, indicating different levels of exposure to the two strains in these individuals. This is the first report of surveillance of antibodies against NV-like viruses in China. The observed high prevalence and early age antibody acquisition suggest that infection by these two human calicivirus strains is common in this population.

[TLC-identification of radix Rehmanniae and its mixed medicinal materials in Pharmacopoeia]

In 237 kinds of medicinal meterials included 71 kinds of Chinese patent medicines composed in Pharmacopoeia such as Liuweidihuang Pills, character identify constituent of Radix Rehmanniae was found by TLC, and was successed to use to identification of Radix Rehmanniae in 10 kinds of Chinese patent medicines such as Liuweidihuang Pills.

[Studies on extracting procedure for huoxue jiangzhi capsules by orthogonal analysis]

The contents of tanshinone IIA, protocatechuic aldehyde and anthraquinone were used to evaluate the extracting procedure for Huoxue Jingzhi capsules by orthogonal analysis. The best one can be described as: the drug powder is reflowed 2 times, 3 hours each, percolated by 80% alcohol with the 4 times weight of powder.